A reflection cup may be arranged on the front of the traditional LED lighting fixture such as a flush light panel or a projection lamp in order to improve the illumination effect of the LED lighting fixture, so that the irradiation area and the irradiation distance of a light source can be effectively improved and the adjustment and control are also more convenient. Moreover, on account of the characteristic of high heat quantity produced when the LED operates, an LED heat sink may be arranged at the rear of the lighting fixture. In general, the heat dissipation of the heat sink is related to the structure and the dissipation area of the heat sink. The most commonly used heat sink currently adopts a fin-type structure or similar structure. The higher the power of LEDs, the larger the volume of the corresponding heat sink. Furthermore, due to the addition of the reflection cup and corresponding components, the lighting fixture may be too large and possible problems may occur in assembly and application. In addition, as for the LED lighting fixture, the higher the power, the larger the heat quantity produced when the LED operates, which is undoubtedly a test for the heat sink. In particular, how to achieve better radiating effect with limited volume is related to whether the lighting fixture can be used stably for a long time and the problems such as the adapting of the lighting fixture to various places and environments.